Portable refrigerator utilizing a living hinge

ABSTRACT

This invention relates to a portable refrigerator having a lowcost cabinet of light weight and good insulating properties and includes a plastic breaker strip and plastic door which utilizes a living hinge disposed between these two elements.

Unite States Patent Lackey et a1, 11911,. H, 197

[54] PORTLE REFRIGERATOR 1 References Cited lI'llULlZlNG A LIVING HlNGEUNITED STATES 1P ATENTS [721 Inventory Mikey, Pimburgh; Jack 2,839,3476/1958 Strub ..312/214 w EXP, Mylo swam 3,009,169 11/1961 B0d116r.......160/231 R mevllle 0f 3,019,486 2/1962 56115011.... ...160/231 R 73Assignee; ,Westinghouse n c -mi p 3,251,382 5/ 1966 Tatsch ..220/9 1FSburgh, p 3,364,298 1/1968 Peters ..49/501 X 3,416,692 12/1968 Cline eta1. ....220/9 F fi J 1970 3,420,363 1/1969 Blickensderfer .220/9 F [21]Appl. No.: 2,850

Primary ExammerJames T. McCall Attorney-F. H. Henson and E. C. Arenz[52] 11.8. C1 ..31l2/214, 312/138 [51] 1m. 1131. ..A25d 111/011 57ABSTRACT [58] Field ofSearch ..312/213,214, 138,257;

62/371, 457 331, 273; 220/9 F; 16/150; 49/DIG 2 This invention relatesto a portable refrigerator having a low- 501, 504 cost cabinet of lightweight and good insulating properties and includes a plastic breakerstrip and plastic door which utilizes a living hinge disposed betweenthese two elements.

12 Claims, 41 Drawing Figures PATENTEU JAN 1 8 M2 SHEET 1 [1F 2 PORTABLEREFRIGERATOR UTILIZING A LIVING HINGE BACKGROUND OF THE INVENTION 1.Field of the Invention This invention relates to a cabinet having thecombination of a door frame and door having a living hinge disposedtherebetween and, more specifically, relates to a low-cost refrigeratorcabinet having a plastic breaker strip and door with a living hingedisposed therebetween.

2. Description of the Prior Art Although the use of small refrigeratorshas increased in recent years, primarily due to their use in trailersand camping vehicles, this increase has been somewhat limited due to thefact that a refrigerator of small size has had a relatively high costrelative to this size, not at all in proportion to what an expectedselling price would be when compared to the selling price of a largeconventional refrigerator. The primary reason for this is the fact thatonly a minimal amount of expense can be removed from the smallerrefrigerator in its manufacture since all the operative components of alarge-sized refrigerator and an insulated enclosure are still requiredin small refrigerators. Thus, the primary savings between a smallrefrigerator and a large one is the reduction in the material cost dueto the smaller dimensions, required for the smaller, portablerefrigerator. These reductions in material and refrigerator componentcost are not significant enough to cause anexpansion of the market forsmall refrigerators to the extent indicated by the interest expressed byconsumers in having convenience type or portable refrigerators of smallsize so that they can be located in the office, family room, den or.game room.

The successful construction of a low-cost refrigerator having lightweight and good thermal insulation is, therefore, a prime requisite forthe successful expansion of the market for such a portable unit.

SUMMARY OF THE INVENTION In accordance with the principles of thisinvention, a compact refrigerator is provided which includes a boxformed from a single piece of foam slab polyurethane or polystyrenematerial having V notches so that the box can be finally formed in asquare configuration. The rear of the refrigerator enclosure is closedby a similar sheet of plastic material which has been formed around theoperating parts of the refrigerator system utilized to cool the interiorspace in the refrigerator. The front of the refrigerator enclosure isclosed by a door also made of a material such as polyurethane orpolystyrene. A door frame of polypropylene or polyethylene or the likehas integrally attached thereto by a living hinge and, advantageouslyformed in the same molding operation, a one piece plastic breaker stripformed of the same material. The door is completed by the inclusion of amagnetic latch on the door frame, with a cooperating magnetic strikelocated behind the plastic breaker strip. Plastic studs may be passedthrough recesses in the corners of the foam slab box so as to hold theplastic breaker strip and rear side of the refrigerator to the foam slabbox.

DRAWING DESCRIPTION FIG. l is a perspective view of the refrigerator ofthe invention showing the major components thereof in exploded view;

FIG. 2 is a perspective view of the refrigerator in assembled condition;

FIG. 3 is a perspective view of the unfolded foam slab making up the boxportion of the cabinet; and

FIG. A is a view taken along line IV-IV oflFIG. I and showing theangular displacement of the breaker strip flange.

DETAILED DESCRIPTION OF THE DRAWINGS In accordance with the principlesof this invention, a portable refrigerator I is provided having lightweight and low cost, and comprising, generally, a combined door andonepiece plastic breaker strip 12, a foam slab box I l and a combinedrear panel with integral refrigeration system I6. These three majorcomponents of the refrigerator may be held in assembled relationship bya series of plastic studs llfl extending through the foam slab box M andinto the rear panel and plastic breaker strip, respectively.

The foam slab box I4 is formed by four sides 20, 22 2d and 26, with thesides 20 and 24 forming the sides of the refrigerator, the side 22forming the top and the side 26 the bottom of the refrigerator. Thesefour sides are integral in that they are all formed from a single sheetof polyurethane or polystyrene (FIG. 3). In the event that polyurethaneis utilized for the sheet and it is formed in the chilled mold process,then no coating need be given to the inner and outer sides of the sheet115 since this material then has a thick impervious skin adjacent itsouter and inner faces and thereby is provided with a substantiallyimpervious inner and outer face in the molding process. If polyurethaneis utilized for the sheet 115, then an outer facing material must beutilized "to protect the relatively soft sheet. For example, a metalsheet of extremely thin gauge and being vinyl clad (not shown) may beprovided so that the outer side of the refrigerator has a facing whichhas some durability.

The single sheet l5 from which the foam slab box M is formed comprises anotched slab which, before folding, has notches 17 that are V-shaped incross section and elongated so as to extend along and between theadjacent lengths of the sides 20, 22, 2A and 26 of the refrigerator. Theends of the sheet 15 include bevels 19,19 that extend for the length ofthe adjacent sides so that the sheet 15 may be properly closed at itsends to form the foam slab box ll l. After the formation of the singlesheet 15 in this manner, it is folded so that a pair of bevel faces 28and 30, for example, formed by either the opposed faces of one of the V"notches. l7 or the bevels R9, of the sheet 115 abut to place sides 20and 22 in a right-angular relationship relative to each other. Aftercompletion of the formation of the square cross section of the foam slabbox M, the said slab box has a fairly rigid and durable configuration,since each of the sides 20, 22, 2d and 2s and their abutting angledfaces reinforce each other and tend to maintain the foam slab box in thecondition illustrated in FIG. 1. The faces formed by the bevels l9,ll9are, of course, held in abutting relationship by an epoxy or adhesiveadapted to the characteristics of either polyurethane or polystyrenematerial.

A front face 32 of foam slab box M provides an inwardly angled flangeface along the front of each of the sides It], 22, 24 and 26 of therefrigerator I'll, these flange faces being indicated 3d, 36, 38 and 40,respectively. Each of these flange faces is disposed substantially at a60 angle to the plane of the outer face of its respective side wall soas to provide a seating and bearing means for the easy nesting of thecombined one piece plastic breaker strip and door frame 12 which aremounted thereon in the final configuration of the refrigerator Ill.

The rear panel and integral mounted refrigeration system 116 includes afoam panel 41 of polyurethane or polystyrene material which is formed ina square configuration so as to mate with the foam slab box 1d. Thisfoam panel has an aperture 42 of generally rectangular shape throughwhich an evaporator M extends. The evaporator 44 may conventionally beone of the operating elements of a refrigeration system 46. In theinvention disclosed, it is contemplated that a typical ammonia-hydrogen,water absorption system be utilized asa part of the refrigerator lb ofthis invention. Such a system is relatively foolproof in operation andrelatively inexpensive for small refrigeration loads. The refrigerationsystem as may utilize a series of coils of steel tubing or the like toform the operating elements of the system; advantageously, however, theuse of an ammonia-hydrogen, water absorption system contemplatesutilization of a pair of integrally connected steel panels which arepressure and heat bonded together to form the evaporator, condenser andabsorber sections of the refrigeration system 46. In such an arrangementas is known in the art, each panel contains a series ofconfigured-groove means .that are in opposed confronting relationshipwhen the panels are integrally connected together so that the groovesform,the closed loop required for the flow of water, ammonia andhydrogen within the system. It should be pointed out that other systemsthan an ammonia-hydrogen, water absorption system may be utilizedto coolthe configuration compartment of the refrigerator l and that theparticular system utilized and-the manner of forming the closed loopdoes not form a part of this invention.

As previously mentioned, the combined rear panel and integralrefrigeration system 16 is physically attached to the slab box 14 bymeans of threaded studs 18. These studs extend through bores 48 formedin the foam slab forming the rear panel 41 and through bores 49 formedby semicircular grooves 51,51 formed in the opposed faces of the Vnotches 17 and the bevels 19. Nuts or the like (not shown) may be usedto pull the foam panel 41 up tightly against the rear side of the foamslab box 14.

The combined one-piece plastic breaker strip and door 12 can be formedby injection molding so as to form an integral assembly including aone-piece plastic breaker strip 50, a door frame 52 and a living hinge105. This integral unit can be conveniently formed from a material suchas polypropylene since the same exhibits relatively high strength butyet has the desired resiliency to operate as a living hinge.

The plastic breaker strip 50 comprises a series of four flange members56, 58, 60 and 62, that are integrally connected together, the flangemembers 56 and 58 forming the sides of the plastic breaker strip 50, theflange 60 forming the top and the flange 62 forming the bottom of theplastic breaker strip 50. As seen in FIG. 1 (see also FIG. 4) each ofthe flange members 56, 58, 60 and 62 is provided with an angularlydirected leg, each leg being indicated, respectively, 64, 66, 68 and 70.The legs 64, 66, 68 and 70 are disposed at an angle similar to theflange faces 34, 36, 38 and 40 so as to be parallel to these faces sothat these legs will seat against their corresponding faces and theouter legs 65, 67, 69 and 71 of the flange members will seat over thesides 20, 22, 24 and 26, with lips (e.g., lip 73) formed on the inwardtermination of legs 64, 66, 68 and 70 abutting against the inside facesof sides 20, 22, 24 and 26 to maintain the position of the plasticbreaker strip 50 relative to the foam slab box 14.

The door frame 52 is also formed from a series of four members 72, 74,76, 78 which are joined integrally at their ends to form a substantiallyrectangular configuration with the members 72 and 74 forming the sidesof the door frame and the member 76 and 78 forming the top and bottomsides of the door frame. Each of these members has a generally channelshape providing a U-shaped cross section with the bight of the U formedat an angle relative to the legs of the U-shape so as to be coincidentwith the angularly disposed legs of the plastic breaker strip 50. Morespecifically, angle faces 82, 84, 86 and 88 are formed respectively onthe members 72 and 74, 76 and 78 for their angled bights. By thisarrangement a door frame 52 is provided having faces which arecoincident with the legs of the plastic breaker strip to provide anesting relationship between the door and the breaker strip when thedoor is closed and to yield a narrow throat clearance between the doorand foam slab box 14 to decrease heat leakage.

The four faces 82, 84, 86 and 88 which form the bight of the channelmembers 72, 74, 76 and 78 have directed inwardly, legs 90, 92, 94 and96, respectively, so as to form an inwardly directed rectangularoutlined aperture within which is disposed a front sheet 98 ofrectangular configuration made of foamed polystyrene or polyurethane.This element is disposed within the channel members 72, 74, 76 and 78and held therein by the U-shape of the channels. The sheet 98 may beeasily assembled within the door frame by mere inward bending of thelegs 90, 92, 94 and 96 and the insertion of the front sheet 98 withinthe resiliently distended channel members 72, 74, 76 and 78 forming thedoor frame 52. A series of front face, inwardly directed legs 89 (onlytwo shown) help maintain the from sheet 98 within the door frame 52.

A boss 100 (FIG. 4) is formed in each corner of the breaker strip 50during the injection molding process so as to threadingly receive a stud18 within the bore 108 formed in each boss. This structural arrangementrigidly holds the breaker strip 50 against the front faces 34, 36, 38and 40 of the foam slab box.

The living hinge means comprises a hinge which may be convenientlyformed integral during the injection molding process with the. breakerstrip 50 and door frame 52. This hinge takes the form of a leaflikeelement extending between the breaker strip 50 and door frame 52 and,more specifically, between angular leg 66 of breaker strip 50 and theangularly disposed face 84 of door frame 52. The hinge 105 is alsoformed of polypropylene with this material being ideal for a hingemember subject to continuous flexing since it has good strength,flexibility and long endurance.

The construction of the refrigerator 10 is completed by the addition ofa magnetic latch 110 mounted on the door frame 52 so as to be incooperative relationship with a magnetic strike 1 12 located behind theplastic breaker strip.

It will be appreciated that, although a single embodiment of theinvention has been disclosed, many modifications could occur thereof toone skilled in the art without the exercise of the inventive faculty.For example, the plastic breaker strip and plastic door frame could beformed individually and then connected together with a thin sheet ofresilient plastic such as polypropylene which would then form the livinghinge. Such an arrangement would still yield the advantage of alightweight, inexpensive door frame and breaker strip assembly. The thinsheet of plastic forming the living hinge, in this case, would be gluedby an epoxy, or the like, to the breaker strip and door frame. Otherobvious modifications could be made to the disclosure of therefrigerator illustrated and described herein which would be obvious topractitioners of the refrigeration art.

What is claimed is:

1. In a refrigerator the combination comprising;

a. a one-piece plastic breaker strip,

b. a door disposed adjacent to said plastic breaker strip,

c. said plastic breaker strip including a front flange extendingangularly inwardly,

d. said door also including faces extending angularly and complementaryto said angularly extending front flange on said plastic breaker strip,

e. a one-piece hinge formed of plastic and attached integrally to atlast a portion of said door and said plastic breaker strip to form aliving hinge therebetween so that said door may move between open andclosed positions,

. said breaker strip being mounted on a foam slab plastic box, said foamslab plastic box forming the compartment for said refrigerator,

g. threaded means extending from said foam slab plastic box forconnection to said plastic breaker strip, and

h. said plastic breaker strip including integral bosses for connectionto said threaded means.

2. In a refrigerator the combination comprising;

a. a one-piece plastic breaker strip,

b. a doordisposed adjacent to said plastic strip,

c. said plastic breaker strip including a front flange extendingangularly inwardly,-

d. said door also including faces extending angularly and complementaryto said angularly extending front flange on said plastic breaker strip,

e. a one-piece hinge formed of plastic and attached integrally to atleast a portion of said door and said plastic breaker strip to form aliving hinge therebetween so that said door may move between open andclosed positions,

f. said breaker strip, said door and said living hinge being made of aplastic resinous material having relatively high strength, highresiliency and durability,

g. said breaker strip, a portion of said door and said living hingebeing made from polypropylene,

h. said breaker strip being mounted on a foam slab plastic box, saidfoam slab plastic box forming the compartment for said refrigerator,

i. said foam slab plastic box being formed from a single sheet of foamplastic having notch and bevel means to enable folding formation of thebox shape,

j. threaded means extending from said foam slab plastic box forconnection to said plastic breaker strip, and

k. said plastic breaker strip including integral bosses for connectionto said threaded means.

3. The combination set out in claim 2 wherein foam slab sheet means areprovided for closing the rear of said foam slab plastic box, and (b)threaded means extend from said foam slab plastic box for connecting itto said foam slab sheet means.

4. The combination set out in claim 3 wherein said threaded means extendcompletely through said foam slab plastic box.

5. The combination set out in claim 4 wherein said foam slab plastic boxconsists of polystyrene.

6. The combination set out in claim 4 wherein said foam slab plastic boxconsists of polyurethane.

7. A refrigerator having;

a. a plastic breaker strip disposed at the front of said refrigeratorand having an aperture therein,

b. a plastic closure member for closing said aperture,

c. a living hinge of plastic material attaching said plastic closuremember to said plastic breaker strip for movement of said closure memberbetween an open and a closed position over said aperture, and d. saidplastic breaker strip, said plastic closure member and said living hingeforming a one-piece unitary assemblywhereby said refrigerator isadaptable to low-cost manufacture.

8. The refrigerator of claim 7 wherein (a) said plastic breaker stripincludes a front flange extending angularly inwardly, and (b) saidclosure member includes faces extending angularly and complementary tosaid angularly extending front flange on said plastic breaker strip.

9. The refrigerator of claim 7 wherein (a) said breaker strip is mountedon a foam slab plastic box, said foam slab box forming the compartmentfor said refrigerator, and (b) said foam slab plastic box being formedfrom a single sheet of foam plastic having notch and bevel means toenable folding formation of said box shape.

10. The refrigerator of claim 9 wherein (a) threaded means extend fromsaid foam slab plastic box for connection to said plastic breaker strip,and (b) said plastic breaker strip includes integral bosses forconnection to said threaded means.

11. The refrigerator of claim 9 wherein (a) foam slab sheet I means areprovided for closing the rear of said foam slab plastic box, and (b)threaded means extend from said foam slab plastic box for connecting itto said foam slab sheet means.

12. The refrigerator of claim 11 wherein said threaded means extendcompletely through said foam slab plastic box.

i =1 i= i

1. In a refrigerator the combination comprising; a. a one-piece plasticbreaker strip, b. a door disposed adjacent to said plastic breakerstrip, c. said plastic breaker strip including a front flange extendingangularly inwardly, d. said door also including faces extendingangularly and complementary to said angularly extending front flange onsaid plastic breaker strip, e. a one-piece hinge formed of plasTic andattached integrally to at last a portion of said door and said plasticbreaker strip to form a living hinge therebetween so that said door maymove between open and closed positions, f. said breaker strip beingmounted on a foam slab plastic box, said foam slab plastic box formingthe compartment for said refrigerator, g. threaded means extending fromsaid foam slab plastic box for connection to said plastic breaker strip,and h. said plastic breaker strip including integral bosses forconnection to said threaded means.
 2. In a refrigerator the combinationcomprising; a. a one-piece plastic breaker strip, b. a door disposedadjacent to said plastic strip, c. said plastic breaker strip includinga front flange extending angularly inwardly, d. said door also includingfaces extending angularly and complementary to said angularly extendingfront flange on said plastic breaker strip, e. a one-piece hinge formedof plastic and attached integrally to at least a portion of said doorand said plastic breaker strip to form a living hinge therebetween sothat said door may move between open and closed positions, f. saidbreaker strip, said door and said living hinge being made of a plasticresinous material having relatively high strength, high resiliency anddurability, g. said breaker strip, a portion of said door and saidliving hinge being made from polypropylene, h. said breaker strip beingmounted on a foam slab plastic box, said foam slab plastic box formingthe compartment for said refrigerator, i. said foam slab plastic boxbeing formed from a single sheet of foam plastic having notch and bevelmeans to enable folding formation of the box shape, j. threaded meansextending from said foam slab plastic box for connection to said plasticbreaker strip, and k. said plastic breaker strip including integralbosses for connection to said threaded means.
 3. The combination set outin claim 2 wherein foam slab sheet means are provided for closing therear of said foam slab plastic box, and (b) threaded means extend fromsaid foam slab plastic box for connecting it to said foam slab sheetmeans.
 4. The combination set out in claim 3 wherein said threaded meansextend completely through said foam slab plastic box.
 5. The combinationset out in claim 4 wherein said foam slab plastic box consists ofpolystyrene.
 6. The combination set out in claim 4 wherein said foamslab plastic box consists of polyurethane.
 7. A refrigerator having; a.a plastic breaker strip disposed at the front of said refrigerator andhaving an aperture therein, b. a plastic closure member for closing saidaperture, c. a living hinge of plastic material attaching said plasticclosure member to said plastic breaker strip for movement of saidclosure member between an open and a closed position over said aperture,and d. said plastic breaker strip, said plastic closure member and saidliving hinge forming a one-piece unitary assembly whereby saidrefrigerator is adaptable to low-cost manufacture.
 8. The refrigeratorof claim 7 wherein (a) said plastic breaker strip includes a frontflange extending angularly inwardly, and (b) said closure memberincludes faces extending angularly and complementary to said angularlyextending front flange on said plastic breaker strip.
 9. Therefrigerator of claim 7 wherein (a) said breaker strip is mounted on afoam slab plastic box, said foam slab box forming the compartment forsaid refrigerator, and (b) said foam slab plastic box being formed froma single sheet of foam plastic having notch and bevel means to enablefolding formation of said box shape.
 10. The refrigerator of claim 9wherein (a) threaded means extend from said foam slab plastic box forconnection to said plastic breaker strip, and (b) said plastic breakerstrip includes integral bosses for connection to said threaded means.11. The refrigerator of claim 9 wherein (a) foam slab sheet means areprovided for closing the rear of said foam slab plastic box, and (b)threaded means extend from said foam slab plastic box for connecting itto said foam slab sheet means.
 12. The refrigerator of claim 11 whereinsaid threaded means extend completely through said foam slab plasticbox.